To Break the Pillars of Heavens

There's a war in Heaven and you've been drafted.

Underworld

The Underworld is a plane of existence serving as the source of souls.

The Underworld is ruled spiritually; the material of the plane responds to the beliefs of its inhabitants. In this way, the plane can have features not normally allowed by physics, such as a large volume being contained in a smaller one.

The Underworld is spoken of as being “below” the World, but this is a symbolic truth, not a literal one; traveling from one to the other does not actually involve a change in elevation.